Glucose, lactose, and saccharose were used as precursors to prepare chars at 400 °C then activated at 800 °C or 1000 °C in closed vessels with controlled amounts of oxygen penetrating through nanopores in the vessel walls. There are correlations between the porosity, amounts of residual O- and H-containing functionalities, and electroconductivity of amorphous carbons studied. The pore size distributions calculated using the nitrogen adsorption isotherms and TEM images show that all carbons are mainly nanoporous with certain contribution of narrow mesopores (at pore half-width x < 5 nm). Oxidizing activation by oxygen penetrating into the closed vessels with chars through nanopores can more strongly change the outer layers of char particles than the inner pores. Therefore, despite relatively great burn-off degree, the textural characteristics are relatively low for activated carbons.Electronic supplementary materialThe online version of this article (doi:10.1186/s11671-016-1723-z) contains supplementary material, which is available to authorized users.

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Transformation of Al(NO3)3∙9H2O (upon heating in the range of 20–1200 °C) into blends of amorphous and crystalline boehmite (210–525 °C), amorphous alumina and crystalline γ-Al2O3 (850 °C), and crystalline α-Al2O3 (1100 °C) was analyzed using X-ray diffraction (XRD), high-resolution transmission electron microscope (HRTEM), infrared (IR) spectroscopy, thermogravimetry, and low-temperature nitrogen adsorption. Boehmite consists of nanoparticles of 6–10 nm in diameter, and part of them has crystalline structure observed in HRTEM images, despite they are XRD amorphous. The nanoglobules are surrounded by amorphous aluminum hydroxide with chains of –AlO(H)–O–AlO(H)– of 1–5 nm in length. Heating of samples at 350–525 °C gives mesoporous aluminum hydroxide with a relatively narrow pore size distribution. An increase in calcination temperature to 850 °C decreases the porosity of alumina composed of amorphous and crystalline (γ-Al2O3) phases. Calcination at 1100 °C gives α-Al2O3 with strongly decreased porosity of aggregates.Electronic supplementary materialThe online version of this article (doi:10.1186/s11671-016-1366-0) contains supplementary material, which is available to authorized users.

The article explores the morphological and electrochemical properties of carbon electrode materials derived from D-lactose by mixing the carbon precursor with an activating reagent selected from the series KOH, K2CO3, ZnCl2, SnCl2 2H2O and calcining the composite mixture at 800 °. After dissolution and removal of K2O, ZnO or SnO from volume of prototypes, the specific surface of carbon materials increases 1.7-4.2 times, and the electrical conductivity-1.4-2.8 times. The activating reagents for effective influence on the properties of carbon structures can be placed in the following order: ZnCl2 > K > K2CO3 > SnCl2 2H2O. It is established that the highest specific capacity as an electrode material for supercapacitor has a sample with the highest electrical conductivity (78 hm-1 m-1) obtained using KOH activating reagent. The electrode material capacity was 176-157 F g-1 at discharge currents of 10-100 mA. It is found that the difference in the values of capacity of prototypes is caused by different chemical state of their surface.